Electrical control system for plural conveyer organization



June 6, 1950 c. o. WOOD msc'mcn. cou'mor. svsmu FOR PLURAL convmmoacmxzxnon Filed Dec. 17, 1945 2 Sheets-Sheet 1 slung (awytyns IITEIM.

3 KER couvmns ZWwm BY M ATTORNEY UTERAL June' 6, 1950 c. o. WOOD2,510,163

smc'mcn. CONTROL svs'rsu FOR PLURAL CONVEYER ORGANIZATION- 2Sheets-Sheet 2 ww'mo ATTORNE Fil ed Dec. 17, 1945 Patented June 6, 1950ELECTRICAL CONTROL SYSTEIVI FOR PLURAL CONVEYER ORGANIZATION Claude o.WootLChicago, m, assignor to Goodman Manufacturing Company, Chicago,111., a corporation of Illinois Application December 17, 1945, SerialNo. 635,562

4 Claims. 1

This invention relates to improvements in electrical control systems forstarting and stopping a plurality of conveyors, one of which dischargesinto the other, in a predetermined sequence.

Conveyer systems used in mines underground have heretofore utilized aplurality of main belt conveyers extending along a main entry of themine and arranged in cascade relation with respect to each other so onewill discharge into the other. with lateral belt conveyers extendingalong the cross entries of the mine for feeding the main line conveyers.These lateral belt conveyers in turn may be fed by room conveyersbringing the coal from the various rooms of the mine.

Various control systems have heretofore been provided for starting andstopping a series of conveyers in mines in a predetermined sequence, soa conveyer will not discharge onto another conveyer which is not inoperation and cause overload of the conveyer which is stopped, andspillage of the coal, but such systems have been dependent uponcontactor controls utilizing time delay relays to delay the timeinterval thatthe next succeeding conveyer starts. Such systems require anumber of control wires which must be brought up to the cross entries tothe starters for the room conveyers, for starting said conveyers,

which wires are live except when the entire conveyer system is out ofoperation.

Such systems, in order to operate properly, also require that thecontrols for one conveyer be connected with the controls for the otherconveyer. The running of a number of control and main power lines to thecross entries and the connecting of the controls for the variousconveyers together is not permitted by the Bureau of Mines, due to thefact that a dangerous condition might be created, which would be apt tocause an explosion.

The principal objects of my invention are to provide a new and improvedform of control system for starting and stopping a plurality ofconveyers in a predetermined sequence, which is safe for operation ingaseous mines and minimizes the number of wires coming into the crossentries and assures that these wires will be dead except when the mainconveyers of the conveyer system are in operation.

Another object of my invention is to provide a new and improved form ofcontrol system for a plurality of conveyers in mines, assuring that theconveyers nearest the dischargepoint start first and stop last, andwhich system is controlled by the speed of travel of the next precedingconveyer so that no lateral or branch conveyer can start until the mainline conveyer into which it discharges is up to speed.

These and other objects of my invention will appear from time to time asthe following specification proceeds and with reference to theaccompanying drawings wherein:

Figure l is a wiring diagram illustrating one form in which my inventionmay be embodied;

Figure 2 is a transverse sectional view taken through a main line beltconveyer and showing a switch operated by the main line conveyer forcontrolling operation of a lateral conveyer;

I Figure 3 is a fragmentary sectional view taken substantially alongline 3-3 of Figure 2; and

Figure 4 is an end view with parts shown in longitudinal section inorder to show the drive from the conveyer belt to the roller for drivingthe switch for controlling operation of the lateral conveyer;

In Figure 1 of the drawings three main belt conveyers III, II and I2 areshown. Said conveyers are arranged in cascade relation with respect toeach other so that the belt I2 will discharge into the belt H, and thebelt II will discharge into the belt l0, and the belt l0 may dischargeinto mine cars, a loading station for loading the coal onto the minecars, or the tipple outside of the mine. A lateral conveyer I3 is shownas discharginginto the main belt conveyer III while a plurality of roomconveyers l4, H are shown as being arranged to discharge into saidlateral conveyer. Said room conveyers as herein shown as being shakerconveyers, but may be any other known form of conveyer for conveyingcoal from the working face of the mine to a cross entry. Also, more thanone lateral conveyer may be provided to discharge onto the main beltconveyer, if desired.

In a like manner, a lateral conveyer i5 is arranged to discharge ontothe main belt conveyer M, and a plurality of branch or room conveyersl6, iii are arranged to discharge onto said lateral conveyer. Similarlya lateral conveyer i1 is arranged to discharge onto the main beltconveyer I2 while a plurality of branch or room conveyers l8, l8 arearranged to discharge onto said lateral conveyer.

The main belt conveyers IO, N and I2 may be of any well known form butare shown in Figure 2 as being troughed belt conveyers wherein a belt l9travels over spaced horizontal idlers 20, 20 and is troughed lbyinclined idlers 2|, 2| supporting its opposite edges. Said idlers aremounted on spaced apart supporting standards indicated generally byreference character 22 and are held in spaced apart relation withrespect to each other by means of spacing members 23, 23, in a mannerwell known to those skilled in the art. In Figure 2 of the drawings ahorizontal roller 24 is shown as being mounted on opposite spacingmembers 23, 23 between the standards 22, 22 on hearing support members25, 25, for supporting an intenmediate portion of the belt between saidinclined idler rollers. Said horizontal roller is rotatably driven bythe belt 59 and is mounted on and drives a transverse shaft 26 connectedwith a roller switch 21. A coupling 28 connects said shaft 26 with ashaft 29 of said roller switch, for driving said switch.

The roller switch 21 is mounted on a plate 30 extending laterally froman intermediate spacing member 23. Said roller switch is herein shown asbeing a well known form of magnetically operated switch and is no partof my invention so need only be shown and described as to its mainoperating parts.

As herein shown, contacts 50, All intermediate the ends of a springcontact strip 31 are engaged with one or the other of spaced contacts M,M mounted on an insulated support 52, to complete a circuit when saidswitch is rotating in one direction or another. The contact strip 3? isflexed to engage a contact 48 with a contact M by means of a magnetizedrotor 33 which rotates an aluminum cup id, on much the same principlesas operate the needle of an automoble speedometer. Said cup is connectedwith the lower end of said spring contact strip by means of a rod 45.Springs 46, 45 connected with centering arms 37, 47 are provided to holdthe contacts 4'0, 40 in a neutral position out of engagement with thecontacts Qt, ii when the conveyer is not in operation.

Since the magnetic operating force of the aluminum cup is dependent uponspeed, a contact 49 is engaged with a contact ll at and above apredetermined speed of rotation of the rotor 43. As the speed of saidrotor decreases, a definite point will be reached where the spring forcewill overcome the magnetic force and disengage a contact 40 from acontact iii. The tension of said springs and the point at which acontact ll! will be moved to engage a contact M may be adjusted bychanging the position of connecting members to, $8, connected to thefree ends of said springs.

In the form of my invention shown in Figure 1 of the drawings, a rollerswitch 49 is driven from the main belt conveyer it and completes acircuit to a control line 50, connected with a starter for the lateralbelt conveyer it, for starting said lateral belt conveyor, when saidmain belt conveyer gets up to speed. Another roller switch 53 is drivenfrom said main belt conveyer Ill and completes a circuit to a controlline 54, connected with a starter 55 for the main belt conveyer ll, whenthe belt conveyer ill gets up to speed, for starting said main beltconveyor. A roller switch 56 is driven from the main belt H andcompletes a circuit to a control line 51, connected with a starter 59for the lateral belt conveyer 55, when the main belt conveyor ii gets upto speed, for starting said lateral belt conveyer. In a like manner, aroller switch 60 connects a control line 6i with a, starter 62 for themain belt l2, for starting said main belt when the belt conveyer Hreaches a predetermined speed.

A roller switch 53 is also provided to complete a circuit to a controlline 64! connected with a starter 65 for the lateral belt conveyer I!when the main belt conveyer l2 reaches a predetermined speed, forstarting said lateral belt conveyer. Where another main belt conveyer is4 provided to discharge into the belt conveyer l2. another roller switchmay be provided to start said main belt conveyer when said belt conveyerl2 gets up to speed.

It should here be understood that the main belt conveyors, the lateralconveyers, and the shaker conveyers are driven by individual m0- torsthrough speed reducers in a well known manner, and that the starters foreach conveyer may be of any form well known to those skilled in the art,which will automatically connect the associated motor to a main powerline and cut out a resistance from said motor to start said motor. Saidstarters and their connections to the conveyer drive motors are no partof my present invention, so will not herein be shown or described indetail.

A starter 61 is provided to start the main belt conveyer Ill. Saidstarter is connected to the positive conductor 69 of a main power line.A control panel indicated generally by reference character 10 isprovided to connect a control line H to'the roller switches 19, 53, 56,6B and 63, and to connect said control line H to said starter Bl, tostart the motor for the main belt conveyer It after said roller switcheshave been connected in the control line circuit. Said control line Hconnects said panel to the positive conductor 6d of the main power linethrough a fuse i2 and control line conductor 13. Said control line H hasa plurality of emergency switches hi, it at various points along itslength, for breaking the circuit to said control line and stopping theentire conveyer system in cases of emergency.

The control panel 7!! may be located in the main entry of a mine wherethe mine is provided with good air and may be totally enclosed in aflame-proof casing. Said control panel, as herein shown, includes amanually operated switch 15, which when closed, closes a circuit fromthe control line ii to an operating coil 16 of a, relay El. This willenergize said coil to close contacts 18 of said relay and close acircuit from the control line H to a control line i9, leading to theroller switch 63, to connect said roller switch in the control linecircuit. Closing of said relay will also close contacts 80 thereof, toclose a circuit to a coil 8! of a time delay relay 82. This willenergize said coil, to close contacts 83 and 8d of said time delay relayand connect the roller switch 58 with the control line it and connect acoil 85 of a time delay relay 86 with the control line H, to energizesaid coil and close contacts Bl and 88 of said relay. This will connectthe roller switches dd and 53 with the control line H and will connect acoil 89 of a time delay relay Ell with said control line, to energizesaid coil and close contacts 99 of said relay. When the relay 90 closes,a circuit will be completed to a control line 92 leading into saidstarter. Completion of said circuit will energize the coils of therelays (not shown) of said starter to close said relays and start themotor which drives the main belt conveyer through a resistance (notshown) and out said resistance out of the circuit to said motor as saidmotor is started. This will connect the starter 61 with the control lineH to energize said starter and start the motor for driving the main beltconveyer Ill.

The time delay relays B2, 86 and 90 are set to open at predeterminedtime intervals after opening of the switch 15, some shaker conveyors l8and the lateral and main line conveyors I1 and I2 will be the firstconveyers to stop and the preceding conveyers will stop in a reverseorder to which they started, so a moving conveyer will never dischargeinto a. stationary conveyer.

When the main belt conveyer I is started in the hereinbefore describedmanner and said belt conveyer gets up to a predetermined speed, thecontacts of the roller switch 59 will close to energize the control line54 and the starter 55 of the main belt conveyer II, to start said beltconveyer. The contacts of the roller switch 49 will then close. Thestarter 55 operates in the same manner as the starter 81. The circuit tothe control line 54 leading to said starter to energize the coils of therelays thereof is, however, closed upon engagement of the contacts ofthe roller the three main belt conveyers are started and switch 58,which is connected in the control line 14 through the relay 85. Saidroller switch is set so that its contacts will close shortly after thecontacts of the roller switch 58 close, so the main belt conveyer IIwill start before the lateral conveyer I3. When the contacts of theroller switch 4'9 are closed, the control line 50 will be energized toenergize the starter 5| and start the lateral belt conveyer I9.

When the main belt conveyer II gets to a predetermined speed, thecontacts of the roller switch 60 will close, to close a circuit to thecontrol line BI and energize the starter 62, to start the main beltconveyer I2. The starter 62 is likewise similar to the starters 55 and61 and the coils of its relays are energized by closin of the rollerswitch 60 which is connected in the control line through the relay 82.The roller switch 56 is set so that its contacts will close shortlyafter the contacts of the roller switch 60 close, to connect theconductor 51 in the control line and energize the starter 59 and startthe lateral conveyer I5.

In a similar manner the roller switch 89 will complete a circuit to thecontrol line 54 when the main belt conveyer I2 gets up to apredetermined speed, to energize the starter 65 and start the lateralconveyer I1.

When the circuit to the control line 50 is completed by the rollerswitch 49, a coil 94 of a contactor 95 will be energized, to close saidcontactor and connect starters 96, 96 for the shaker conveyers I4, I4 tothe main power line 69 through a conductor 91. A separate roller switch99 is provided for each starter 96. Said starters 96, 96 are similar tothe starters B1 and 5I with the exception that they are connecteddirectly to the main power line rather than to a control line as aresaid starters 61 and 5I. The coils of the relays of said starters 98, 96are energized to complete a control circuit within said starter andcomplete a circuit to the motors for driving the room conveyers and cutout a resistance therefrom as said motors are started, as said rollerswitches 99, 99 rotate at a predetermined speed and close theircontacts. Said roller switches are driven by the belt of the lateralconveyer I3 and are arranged to complete a control circuit to theirassociated starter 96, to start the motors for driving the shakerconveyers I4, I4 when said lateral conveyer I9 reaches a predeterminedspeed. Said roller switches may be so set that one branch shakerconveyer will start ahead of the next succeeding conveyer, to enable thelateral conveyer to clear itself of loose material that may be leftthereon and to be evenly loaded and also to prevent heavy startingcurrent surges. As herein shown the shaker conveyers I4, I4 are timed tostart after after the lateral conveyer It has started and come up tospeed.

Starters I00, I00 for the shaker conveyers I 5, I8 are connected to themain power line, when the control line circuit has been completed to thecontrol line 51 and starter 59, by means of a contactor IOI. Saidstarters I00, I00 like the starters 98, 98 are directly connected to themain power line and start said shaker conveyers in a manner similar tothe shaker conveyers I4,. I4 by roller switches I02, I02 arranged tocomplete control circuits within said starters I00, I00 from said mainpower line to the motors for driving said shaker conveyers, when thelateral conveyer I5 starts and reaches a predetermined speed.

In a similar manner the shaker conveyers I8, I8 are started by rollerswitches I09, I08 driven by the lateral conveyer I1 and completingcircuits within starters I04, I04 in the same manner the controlcircuits to the starters 99, 99 and I02, I02 are completed forconnecting the motors for said shaker conveyers in the main power line,for starting said shaker conveyers, upon the closing of a contactor I05,when the lateral belt conveyer I1 attains the required speed.

A local control switch I05 is provided for each main belt conveyerstarter to permit the associated belt conveyer to be started when themine is down and the other conveyers of the system are not in operation,in cases where it might be desired to repair the conveyer or beltwithout startin the rest of the conveyers in the system. In a similarmanner, a local control switch I01 is provided for each lateral conveyerstarter, to connect said lateral conveyer starter to the control line Hindependently of the main belt conveyer, to start said lateral conveyerand its associated shaker conveyers at times when the mine is down andit is desired to repair the lateral conveyers or the shaker conveyersdischarging into said lateral conveyers.

A series of lights is provided to indicate when the main belt conveyersare operating and when the last lateral conveyer of the system is inoperation. Said series of lights includes a light I09 at the drive endof each main belt conveyer which is connected to the starter 61 for theconveyer I0 through a conductor IIO, which will light when said conveyeris in operation. It also includes a light III at the drive end of eachmain belt conveyer which is connected to the starter 55 for the conveyerII through a conductor H2, which will light when said conveyer is inoperation. A light II3 connected to the starter 62 through a conductorH4 is also provided at the drive end of each belt conveyer, which willlight when the conveyer I2 is in operation. Lights II5 connected to amain power line H8 and arranged to light when the contactor I05 closesand the lateral conveyer I1 has been started and power is connected tothe shaker conveyers I8, I8, are also provided and are adapted to lightwhen the lateral conveyer I1 is in operation and the circuit to theshaker conveyers I8, I8 is closed. Thus if any of the aforementionedconveyers should stop, the light connected with the starter for saidassociated conveyer will go out, to serve as a warning, and all of theconveyers discharging into conveyer which has stopped will also stop.

It should here be noted that while the first conveyer in the line ofconveyers always starts first, that when the switch 15 is opened thecircuit to 7 the coil 1 of the relay II will be opened to cause thecontacts of said relay to open and open the circuit to the control lineI! and disconnect the roller switch 63 from the control line H to stopthe lateral belt conveyer l1 and the shaker conveyers l8, ll. It willalso open the circuit to the coil 8| of the time delay relay 82, thecontacts of which will open after a predetermined time interval, todisconnect the roller switches 56 and I from the control line H, tostop' the shaker conveyers l6. l6, lateral belt conveyer l5, and themain belt conveyer R. It will also open a circuit to deenergize a coilof the time delay relay 86 to open said relay after a predetermined timedelay interval and disconnect the roller switches 49 and SI from thecontrol line H, to first stop the main belt conveyer II and then stopthe shaker conveyers ll, i4 and the lateral conveyer It. It will alsoopen the circuit to the coil as of the time delay relay 80, the contactsof which will open after a predetermined time interval to disconnect thestarter 61 from the control line H, and stop the main belt conveyer iii.

A simplified system for controlling operation of a number of conveyershas thus been provided which is safe for operation in mines and which isso arranged that the first conveyer in the line is the first to startand the last to stop, and is also so arranged that the conveyers arestarted by control means dependent upon and controlled by the speed ofthe next preceding conveyer, so that it is never possible for oneconveyer to discharge into a conveyer which is not in operation.

While I have herein shown and described one form in which my inventionmay be embodied, it will be understood that the construction thereof andthe arrangement of the various parts may be altered without departingfrom the spirit and scope thereof. Furthermore, I do not wish to beconstrued as limiting my invention to the specific embodimentillustrated, excepting as it may be limited in the appended claims.

I claim as my invention:

1.. In an explosion-proof electrical control system for controllingoperation of a series of conveyers, one discharging into the other, andin cluding a plurality of main line conveyers, a separate starter forstarting each of said main line conveyers, a plurality of lateralconveyers dis charging into said main line conveyers, a sep-= aratestarter for starting each of said lateral con-= veyers, a main powerlineconnected with each j oi. roller switches driven by said main lineconveyers, certain oi said roller switches being adapted to connect thestarters to the next succeeding main line conveyers to said control lineand certain other of said switches being adapted to connect the startersto said first lateral conveyers to said control line when said main lineconveyers into which said lateral conveyers discharge reach apredetermined speed, a control panel having a manually operated switchfor connecting said panel to said control line, said control panel alsoincluding a relay for each main line conveyer, for connecting saidroller switches driven by said main line conveyer to said control lineupon closing of said starting switch and a relay for connecting saidfirst main conveyer starter to said control line to start said firstmain line conveyer.

2. In an explosion-proof electrical control system for controllingoperation oi a series or con- 8 veyers, one discharging into the other,and including a plurality of main line conveyers, a separate starter forstarting each 0! said main line conveyers, a plurality of lateralconveyers discharging into said main line conveyers, a separate starterfor starting each of said lateral conveyers, a main power line connectedwith each of said starters, a control line, and means for starting saidmain line and lateral conveyers in av predetermined sequence including aplurality of roller switches driven by said main line conveyers, certain01 said roller switches being adapted to connect the starters to thenext succeeding main line conveyers to said control line and certainother 01' said switches being adapted to connect the starters to saidfirst lateral conveyers to said control line when said main lineconveyers into which said lateral conveyers discharge reach apredetermined speed, a control panel having a manually operated switchfor connecting said panel to said control line, said control panel alsoincluding a relay for each main line conveyer, for connecting saidroller switches driven by said main line conveyer to said control lineupon closing of said starting switch, and a relay for connecting saidfirst main conveyer starter to said control line to start said firstmain line conveyer, said relays with the exception of the relayconnecting the roller switch controlling operation of the last conveyerin the series being time delay relays so arranged -as to open atpredetermined time intervals after the circuit thereto has been broken,to cause the conveyers to stop in a progressive order starting with thelast conveyer.

3. In an explosion-proof electrical control system for controllingoperation of a series of conveyers, one discharging into the other, andincluding a plurality of main line conveyors, a separate starter forstarting each of said main line conveyers, a plurality of lateralconveyers discharging into said main line conveyers, a separate starterfor starting each of said lateral conveyers. a main power line connectedwith each of said starters, a control line, and means for starting saidmainline conveyers and said lateral conveyers in a-predeterminedsequence including a plurality of roller switches driven by the first01' said main line conveyers, a plurality of roller switches driven bysaid next succeeding main line conveyer, certain of said roller switchesbeing adapted to connect the starters for the next succeeding main lineconveyer to the control line, when said next preceding main lineconveyer reaches a predetermined speed, and certain other of said rollerswitches being adapted to connect the starters for said associatedlateral conveyers to said control line when the associated main lineconveyers reach a predetermined speed, a control panel having a manuallyoperated switch for connecting said panel to said control line, saidcontrol panel also including a relay for connecting said starter forsaid first main line conveyer to said control line, to start said firstmain line conveyer, and a separate relay for each pair of rollerswitches, for connecting said roller switches to said control line tostart said next succeeding main line conveyers and said lateral conveyerin a predetermined order after said first main line conveyer has reacheda predetermined speed.

4. In an explosion-proof electrical control system for controllingoperation of a series of conveyers, one discharging into the other, andincluding a plurality of main line conveyers, a separate starter forstarting each of said main line conveyers, a plurality of lateralconveyers dis- 9 charging into said main line conveyers, a separatestarter for starting each of said lateral conveyers, a main power lineconnected with each of said starters, a control line, and means forstarting said main line conveyer and said lateral conveyer in apredetermined sequence including a plurality of roller switches drivenby the first of said main line conveyers, a plurality of roller switchesdriven by said next succeeding main line conveyer, certain of saidroller switches being adapted to connect the starters for the nextsucceeding main line conveyer to the control line; when said nextpreceding main line conveyer reaches a predetermined speed, and certainother of said roller switches being adapted to connect the starters forsaid associated lateral conveyors to said control line when theassociated main line conveyers reach a predetermined speed, a controlpanel having a manually operated switch for connecting said panel tosaid control line, said control panel also including a relay forconnecting said starter for said first main line conveyer to saidcontrol line, to start said first main line conveyer, and a separaterelay for each pair of roller 10 switches, for connecting said rollerswitches to said control line to start said next succeeding main lineconveyers and said lateral conveyer in a predetermined 0 er after saidfirst main line conveyer has reac ed a predetermined speed, said relayswith the exception of the relay connecting the roller switch of the lastconveyer in the series being time delay relays 50 arranged as to openafter predetermined time intervals after the circuit thereto has beenbroken, to cause the conveyers to stop in a progressive order startingwith the last conveyer.

CLAUDE 0. WOOD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,620,531 Fisher Mar. 8, 19272,371,956 Deea Mar. 20, 1945 2,372,130 Smith Mar. 20, 1945 2,372,131Smith Mar. 20, 1945

